'\" t
.\"     Title: enosys
.\"    Author: [see the "AUTHOR(S)" section]
.\" Generator: Asciidoctor 2.0.20
.\"      Date: 2025-01-13
.\"    Manual: User Commands
.\"    Source: util-linux 2.40.4
.\"  Language: English
.\"
.TH "ENOSYS" "1" "2025-01-13" "util\-linux 2.40.4" "User Commands"
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.SH "NAME"
enosys \- utility make syscalls fail with ENOSYS
.SH "SYNOPSIS"
.sp
\fBenosys\fP [\fB\-\-syscall\fP|\fB\-s\fP \fIsyscall\fP] command
.SH "DESCRIPTION"
.sp
\fBenosys\fP is a simple command to execute a child process for which certain
syscalls fail with errno ENOSYS.
.sp
It can be used to test the behavior of applications in the face of missing
syscalls as would happen when running on old kernels.
.SH "OPTIONS"
.sp
\fB\-s\fP, \fB\-\-syscall\fP
.RS 4
Syscall to block. Can be specified multiple times.
.RE
.sp
\fB\-i\fP, \fB\-\-ioctl\fP
.RS 4
Ioctl to block. Can be specified multiple times.
.RE
.sp
\fB\-l\fP, \fB\-\-list\fP
.RS 4
List syscalls known to \fBenosys\fP.
.RE
.sp
\fB\-m\fP, \fB\-\-list\-ioctl\fP
.RS 4
List ioctls known to \fBenosys\fP.
.RE
.sp
\fB\-h\fP, \fB\-\-help\fP
.RS 4
Display help text and exit.
.RE
.sp
\fB\-V\fP, \fB\-\-version\fP
.RS 4
Print version and exit.
.RE
.SH "EXIT STATUS"
.sp
\fBenosys\fP exits with the status code of the executed process.
The following values have special meanings:
.sp
\fB1\fP
.RS 4
internal error
.RE
.sp
\fB2\fP
.RS 4
system does not provide the necessary functionality
.RE
.SH "AUTHORS"
.sp
.MTO "thomas\(att\-8ch.de" "Thomas Weißschuh" ""
.SH "SEE ALSO"
.sp
\fBsyscall\fP(2)
.SH "REPORTING BUGS"
.sp
For bug reports, use the issue tracker at \c
.URL "https://github.com/util\-linux/util\-linux/issues" "" "."
.SH "AVAILABILITY"
.sp
The \fBenosys\fP command is part of the util\-linux package which can be downloaded from \c
.URL "https://www.kernel.org/pub/linux/utils/util\-linux/" "Linux Kernel Archive" "."